with aches, fever and chills- the flu's a really big deal. so why treat it like it's a little cold? there's something that works differently than over-the-counter remedies. prescription tamiflu attacks the flu virus at its source. so don't wait. call your doctor right away. tamiflu is prescription medicine for treating the flu in adults and children one year and older whose flu symptoms started within the last two days. before taking tamiflu tell your doctor if you're pregnant, nursing. have serious health conditions, or take other medicines. if you develop an allergic reaction, a severe rash, or signs of unusual behavior, stop taking tamiflu and call your doctor immediately. children and adolescents in particular may be at an increased risk of seizures, confusion or abnormal behavior. the most common side effects are mild to moderate nausea and vomiting. the flu comes on fast, so ask your doctor about tamiflu. prescription for flu.